Electron diffusivities in MgB2 from point contact spectroscopy -: art. no. 224506

被引：16

作者：

Bugoslavsky, Y ^{[1
]}

Miyoshi, Y

Perkins, GK

Caplin, AD

Cohen, LF

Pogrebnyakov, AV

Xi, XX

机构：

[1] Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BZ, England

[2] Penn State Univ, Dept Phys, University Pk, PA 16802 USA

[3] Penn State Univ, Mat Res Inst, University Pk, PA 16802 USA

来源：

PHYSICAL REVIEW B | 2005年 / 72卷 / 22期

基金：

美国国家科学基金会;

关键词：

D O I：

10.1103/PhysRevB.72.224506

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We quantify the underlying physical mechanism behind the variation of the Andreev reflection with applied magnetic field in MgB2 epitaxial film and find good agreement with the theory for a dirty two-band superconductor. The important microscopic property, the ratio of electron diffusivities in the sigma and pi bands can be measured directly by means of Andreev reflection. We analyze results obtained for different directions of the applied field and determine the anisotropy of the diffusivities demonstrating that the anisotropic upper critical field is determined solely by the anisotropic diffusivity in the sigma band.

引用

页数：5

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